Deuteronomy 7:7–9,
It was not because you were more in number than any other people that the LORD set his love on you and chose you, for you were the fewest of all peoples, but it is because the LORD loves you and is keeping the oath that he swore to your fathers, that the LORD has brought you out with a mighty hand and redeemed you from the house of slavery, from the hand of Pharaoh king of Egypt. Know therefore that the LORD your God is God, the faithful God who keeps covenant and steadfast love with those who love him and keep his commandments, to a thousand generations
The theology of election leads to the exhortation to know the very character of God. He is sovereign: loving whom he loves, having mercy on whom he wills — and he is not arbitrary. He acts in accordance to a standard, namely, himself. He is a God of covenant faithfulness.
This passage is a remarkable blending together of YHWH’s utter sovereignty and condescending relation to his people. He is sovereign enough to choose whom he wills, according to his own good pleasure, and yet he is guided by his own character such that he never acts outside of who he is. He is sovereign, in that he does whatever he pleases, and he is bound, in that he doesn’t contradict his character.
This is deeply rooted in the essence of the triune God, whose election is in reference to the Son (Ephesians 1:4). And the root of his election — his unconditional, because-he-is-God election — and his mind-boggling, mouth-shutting faithfulness is intrinsic to himself. It is in himself, “for he is content with his own secret good pleasure.”